Building Portable Thread Schedulers for Hierarchical Multiprocessors: the BubbleSched Framework

Samuel Thibault (1, 2) , Raymond Namyst (1, 2) , Pierre-André Wacrenier (1, 2)

1 RUNTIME - Efficient runtime systems for parallel architectures
2 LaBRI - Laboratoire Bordelais de Recherche en Informatique

Exploiting full computational power of current more and more hierarchical multiprocessor machines requires a very careful distribution of threads and data among the underlying non-uniform architecture. Unfortunately, most operating systems only provide a poor scheduling API that does not allow applications to transmit valuable scheduling hints to the system. In a previous paper, we showed that using a bubble-based thread scheduler can significantly improve applications' performance in a portable way. However, since multithreaded applications have various scheduling requirements, there is no universal scheduler that could meet all these needs. In this paper, we present a framework that allows scheduling experts to implement and experiment with customized thread schedulers. It provides a powerful API for dynamically distributing bubbles among the machine in a high-level, portable, and efficient way. Several examples show how experts can then develop, debug and tune their own portable bubble schedulers.

Mots clés: Threads; Scheduling; Bubbles; NUMA; SMP; Multi-Core; SMT

Domaines: Calcul parallèle, distribué et partagé [cs.DC]

Samuel Thibault, Raymond Namyst, Pierre-André Wacrenier. Building Portable Thread Schedulers for Hierarchical Multiprocessors: the BubbleSched Framework. EuroPar, Aug 2007, Rennes, France. ⟨10.1007/978-3-540-74466-5_6⟩. ⟨inria-00154506⟩